Tension device



E. P. HOPKINS. TENSION DEVICE. APPLl CATl0N FILED IAN- 2, 1913. RENEWED JUNE 28.15MB.

Patented Aug. 23, 1921.

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UNITED STATES PATENT OFFICE.

EDWARD rowan. nozmms, or NEW you, n. Y., assrenoa T was runms'nnm urrLrrmsco, or NEW YOItK, N. Y.,' A conrom'rron or new DEVICE.

' Specification of Letters Patent.

Patented Aug. 23, 192 1.

llipllcatiennledlanuary 2, 1918, Serial No. 739,715. ReuewedJune 1918. 7 Serial No. 242,504.

To-all whom it may concern:

Be it known that I, En'wam) POWELL Hor- KINS, a subject of the Kin of Great Britain residin .at the city of ew'York, State of New 'Y irk, United States of America, have invented new and useful Improvements in Tension -Devices,- of which the following is a-full, clear, concise, and exact description, "reference being 1 had to the accompanying drawing, forming a art of this specification.

This invention re atesito tension devices.

l The web 'orfabric which is operated upon by printin pressesand the likeisgenerally drawn mg the machinev fromj-a roll. The tension of the web tends to yaryfrom many -causes such as changes in. the s dof the ress orjchange in t-he diameterv of the roll.

t i'simportant that an even tension'be maintained onthe web andth'atany tendencytof the tension to vary be immediately and posi .tively compensated for. To' tlus end the present invention has been devised.

One of the objects of this invention is to providean improved means for automatically maintaimng a' uniform tension on a web undei-all operating conditions Another object isto provide a positive and sensitive means for automatically regulet gthe tension on a 'webas it is drawn into. ress. 1

- Anot er o ject is to provide an improved means which'will automatically regulate the v tension of al web and prevent overrunning of the web' rolLf, I

Other, objects and advantages of the invention will hereinafter appear. 1 One embodiment offlthe invention as ap: plied to a. printing press is shown in the ac-' companying drawmgs,in;which- Figure 11s a front elevation, and I Fig. is'an end elevation. I heitgbrolll supported on a spindle 2. The spindle 2'has its bearings in brackets 3 on the supportin' .frame.4. The web is drawn from the m1 1',:ove'r, atension roll 5, tension controlling rolls Gland 7 and guide roll 8 into the press.

The spindle'2. carries a friction drum 9 ooved, as. shown-at 10 to cotiperate with riction brake shoes 11, V-shapedin crosssection. The friction shoes are pivoted to levers 12 and 13 which are fulcrumed re spectively at 14 and 15 on a cross-link 16. Cross-link 16 is supported by an adjustable screw 17 entering a socket in the frame 4.

in' length by means ottlie screw}coupling.22

operated yl the hand-wheel 23..

A" link 27 connects the free end of com-y pound lever 1? withapin 28 projectingffrom. an arm 29 which is. fast on one endfof a rock shaft 30. Rock shaft .30 carries,-.ateach enda pair of arms 31 and 32mouiitedtfast, there on and extending in op site radial directions therefrom.v Arms and 32 ca the tension controllingro'lls 6 and 71 respectively. Rotat on of the rockshaft 3,0 idafcounter clock-wise direction will exert a downward thrust on link 27 whichwill act through the levers and links described to cause. thefriction shoes to exert a powerful braking action on the roll spindle.

- A predetermined imn ai raking action is obtained by means of a'spring 33 adjustable by a hand-wheel 34. :Spring 33 exerts its force through a' link 36 connected to pin, 28 to cause the link 2 7 to apply thebrake; The brake may be released manually by the hendle '37 onthe. arm 29.- A latch 38 cooperat In"ope ration the spring j33 is eicert The tension roller 5 is mounted in slid- '95 sufiicient braking action, onthe roll spindle to maintain the required tension on the-web as it is drawnl into .;the press; vThe'actiouof the counteracted to acertainei'rtent by thejtension on the web which gtends'to rock the shaft 30 in a clock-wisevdirection. .An

tendency to increase the tension on 'thewe will still further rock the shaft-B0 clockwise and raise up on the lever 19 .to' decrease the braking action, while any tendency to de crease the tension on the web will act in the reverse direction to increase the' brakin action. A tendency to vary the web tension occurs when the press speed is; changed as. I

when the press is suddenlystarted or when 29 e e eh i a 1 syn 4 ,,,i J KW i i its ope'ratiriispeed is suddenly increased or decreased. tendency to change the tension also: results from jthedecrease" 1n .the size of the roll as the Aveb is -clra'wnoli, a smaller roll, of course, requiring a greater'pull on I the web to obtain the same linear speed as: the web passes into the press. Upon breakage ofthe' web' obstoppage of the'p'ress the full strength of spr ggfiq yvil l "be. imme-, 1o diately afi'pliedto set,the='brake to prevent overrunmng of, the roll, The tensionroll 5 ',com'pensates' for' slight fluctuations in tension on" the v'vveb', s'uc ,for example, I as may caused by the flattened portions on a,-ro'l 1, The tension eoijtrolrollersgbothtactingon the brahfni echanisxn and being positioned ndrm e' fle -t .nsbie nsin deflection; there6f,,1 lll ow -.de\liutio ns in-i aveb tension tojexe'rt e1 multiplied ejfct upon: the

oresen's tiveyand reliable tensl produced; I WhatI'claI as eyv; dgdesn-e to secure fie i-roll' shaft enacts-em nent: a ro ks e s sprig-om the shaft rat eaeh side :of the. path of "the web, two; f'displaceable, guiderollerscar- ,ried by the pairs; ofarmsto receiveithe web At ained under land over them respectively, a

hand leuenfei'rtending fmmjthe; rock-shaft, and a .conne tingrodm rtending downward 2. In a web. tension inechanism-,-tne ;com-

-.hina.ti on' of impair of. frame luprig'htsiearr ing supports ,fo iawebrroll shaft,- azbm e 40 for said' shaftgsaif transverse rock -shaft mounted inbracke'ts upo'nthe pressside of e said .uprights almve' the 'web, ,two :arms' ex teuding; ,in different idirectioris from the shaft .at each 'side of the ,patherif ithe web,

two displaeeable guide: rollers.carriedbyt'he l pane oi arlms toreceive-the 'web trained linden and; overtliem.;respectively,' a lever cxtendingfrom said rock-shaft beyond the web-roll side of the uprights, akam-necting red extending downward from said 1mm,

the brake, auothenrikl also extending -doivn- .ward from tlielevtT-htuthe opposite side of one of. theiiprights-fimhnthe rmlc-sh'zrft; an abutmentbracket projecting V rem said upposed 1x:tweenbracket. 3. Awveh tensionmeqi alize or' printing pressesand the-like, adapted to maintain a id rod" substantial lyconstant web tension 1 in a-r'w'eb continuously imovable',comprising a web roll shaft, :a brake associated with said shaftto vary 5 thez'tension in v the web, a pair: of- :web guides rotatable about a: ,common={axis T and 5,65 upon WhichLthe ebiacts toproduce a-couple rodr A web-tension equalizer for printing presses, adapted-to maintain substantially ec 'nisni is thereby 'e aa'; tof itid-gbiake mechanism,

about the common axis, and a lever system interlinkingsaid brake and said gui es,.to

-transmit the effect of varying web tension to the brake to provide corrective influences ,to maintain uniform web tension.

4. In a'web tension mechanism, the combination of a frame having a isuo'port for a web-roll shaft, the Web-roll shaft bearing a brake pulley, opposed levers barr ying brake shoes, a fulcrum link connecting said levers at one end, an actuating lever pivotally connectedwvith one ofthe brake levers", a'link connectin said actuating lever-and the other pf the bra e levers, a connecting rod extend- -1ng upward from said actuating lever, and a web contr'olleddevice connected ivit'h' said uniform web tension in a relatively hig speed continuously movable" Web, the said equalizer -comprising a shaft" for supporting a web froll, a brake mechan sm associated with the shaft, the said brake mechanism in "eluding friction members, and I aresilient means normally actinggtorapply the friction members tothe shaft, a pair of-weli "guides flected path toproduce a couple about the common aitis. means for "transmitting the movement of the pair of Web guides to the brake niechamsm"whereby the said move- ,ment feuds to neutralize the effect of theresilient member so that the effect of the bodily rotatable web guides is to produce a multiplied eflect of the web tension to act'in oppositionto the tension member whereby substantially uniform web tension ismaintained.

6. A web tension equalizer for prlntin presses wherein a continuously movable We is witluirawvri-from a web roll, the said equalizer comprisinga web roll shaft, a brake mechanism associated w th the' shaft including friction members, a resilient member, and means connecting the friction members and theresilient member whereby the bodilyd'otatable about a'common weird ladapted' to guide the web in akloubly de said friction members normally not to restrain the shaft'against rotation, a 'pair of guide rollers, an 'arm' 'connect1ng' the guide rollels and haying a pivotal support there betiveeh. the said guide'rollers being bodily rotatable"aboutthe pivotal support, means conn' rti riisin, the

.said guide. rollers funetioning to 'glthe armandtheqbrake mecha- I web roll, a web tension equalizer comprising members, a resilient member, means connect-.

ing the friction members and the resilient member whereby the saidfriction members normally tend to restrain the shaft against rotation, and means for ad'usting the resilient'member to vary the e ective brake ten sion, a pair of web guide" rollers, an arm connecting the guide rollers and having a pivotal support therebetween, the said guide rollers being bodily rotatable about the pivotal support, means connecting the arm and 16 brake mechanism, the said guide rollers functioning to guide a web in a doubly deflected path so that the web tension acting upon the bodily rotatable rollers forms a couple about the point of pivotahsupport 20 the efiect of whichis to multiply the web tension so that the effect of the couple may be transmitted to the braking mechanism to act in opposi ion to the resilient member so that sensitive braking action is obtained to maintain substantially uniform web tension,

the said adjusting means functioning inde-' pendent of the weight of the web guides and the arms connecting'the same, and to compensate automatically for worn friction members.

8. A web tension mechanism comprising a web roll shaft, a brake therefor, a web control for the brake having a rock shaft. a plurality of arms extending in different direc- 36 tions from the shaft at each side of the path of the web, and guide rollers caried by the arms and arranged to receive the web umler and over them respectively, a tension roll over-which the web is received as it passes from the web roll tothe guide rollers. means-'- for maintaining the tension roll in yielding contact with the web. adjustable yielding means cooperating with the brake and maintaining. a predetermined initial tension in the web, and means connecting the arms and the brake for transmitting movement from the rollers to the brakes 9. A web tension equalizer for maintaining a substantially constant tension in a continuously moving web. comprising a web roll shaft, a brake therefor tor\'ar \;ing the tension in the web, a pair of web guides rotatable about a common axis and upon which the web acts to produce 'a couple about a given axis, a tension roll arranged in the path of the web. means for maintaining the tension roll in yielding contact with the web. adjiis zilvlc yielding means cooperating with the brake and maintaining. apredetermined initial tension in the web, and a lever system intcrlinking the brake and the guides to transmit the effect of varying web tension to the brake to provide corrective influences 'to maintain substantially uniform wcb tension.

In witness whereof. l have hereunto subscribed my name in the presence of two witnesses;

' EDWARD POWELL HOPKINS. Witnesses Ram-n W. lhimiouons. 

